1. Field of the Invention
The present invention relates to a robot control, and more particularly, to a robot localization system for controlling a position and an orientation of a robot.
2. Description of the Related Art
Methods or apparatuses for localization of a robot uses dead-reckoning such as odometry and inertial navigation, for measuring a relative position of a robot; a global positioning system (GPS), active beacons, etc., for measuring an absolute position of a robot; and a magnetic compass for measuring an absolute orientation of a robot. Approaches for robot localization are described in detail in “Mobile Robot Positioning Sensors and Techniques” by J. Borenstein, H. R. Everett, L. Feng, and D. Wehe.
FIG. 1 is a diagram illustrating a conventional technique of detecting a position of a robot using three beacons. Positions A and B are detected using beacon 1 and beacon 2. Accordingly, beacon 3 is required to exactly detect the position A. The GPS is based on this principle. However, only positions without an orientation can be detected with this conventional technique.
Korean Patent Publication No. 2000-66728, entitled “Robot Having Function of Detecting Sound Direction and Motion Direction and Function of Automatic Intelligent Charge and Method of Controlling the Same,” discloses an algorithm for measuring a sound direction and controlling the robot to move to an automatic charger. When the charger generates a sound having a particular frequency, the robot detects a direction of the sound, locks on the detected direction, and docks to the charger. According to this technique, only a motion direction of a robot can be measured and controlled.
Korean Patent Publication No. 2002-33303, entitled “Apparatus for Detecting Position of Robot in Robot Soccer Game,” discloses an apparatus for detecting a position of a robot using a plurality of beacons. Here, only positions without an orientation are detected.